In Utero Gender Dimorphism of Adiponectin Reflects Insulin Sensitivity and Adiposity of the Fetus

Circulating adiponectin reflects the degree of energy homeostasis and insulin sensitivity of adult individuals. Low abundance of the high molecular weight (HMW) multimers, the most active forms mediating the insulin‐sensitizing effects of adiponectin, is indicative of impaired metabolic status. The increase in fetal adiponectin HMW compared with adults is a distinctive features of human neonates. To further understand the functional properties of adiponectin during fetal life, we have evaluated the associations of adiponectin with insulin sensitivity, body composition, and gender. Umbilical cord adiponectin, adiponectin complexes, and metabolic parameters were measured at term by elective cesarean delivery. The associations between adiponectin, measures of body composition, and insulin sensitivity were evaluated in relation to fetal gender in 121 singleton neonates. Higher total adiponectin concentrations in female compared with male fetuses (34.3 ± 9.5 vs. 24.9 ± 8.6, P < 0.001) were associated with a 3.2‐fold greater abundance in circulating HMW complexes (0.20 ± 0.03 vs. 0.08 ± 0.03, P < 0.001, n = 9). Adiponectin was positively correlated with neonatal fat mass (r = 0.27, P < 0.04) and percent body fat in female fetuses (r = 0.28, P < 0.03) and with lean mass in males (r = 0.28, P < 0.03). There was no significant correlation between cord adiponectin and fasting insulin concentrations or fetal insulin sensitivity as estimated by homeostasis model assessment of insulin resistance (HOMA‐IR). The gender dimorphism for plasma adiponectin concentration and complex distribution first appears in utero. In sharp contrast to the inverse correlation found in adults, the positive relationship between adiponectin and body fat is a specific feature of the fetus.     

Pest Responses to Odors From Predators Fed a Diet of Target Species Conspecifics and Heterospecifics

ABSTRACT Research into the use of predator-odor-based repellents as a management tool has gained momentum during the past 30 years. Some studies have suggested that odors from a predator whose diet includes the target species are more effective than odors from a predator that does not consume the species. To evaluate this management tool in the Australian context and to determine the effect, if any, of predator diet on odor repellence, we tested eutherian and metatherian, predator fecal odors on phylogenetically separated pest species that currently occur in Australia. We evaluated fecal odors from tigers (Panthera tigris) and Tasmanian devils (Sarcophilus harrisii) as repellents for goats (Capra hircus) and eastern grey kangaroos (Macropus giganteus). We fed tigers and Tasmanian devils 2 diets: one of goat and one of eastern grey kangaroo. The test fecal odors were more effective than a control odor of carrier material and solvent at deterring goats (P < 0.001) and kangaroos (P = 0.02) from food. Tiger fecal odor was more effective than Tasmanian devil odor in deterring both goats (P = 0.001)and kangaroos (P = 0.03). We observed a decrease in the number of feeding events for goats when they were exposed to the odor from a tiger fed goat compared with all other predator-diet combinations (P < 0.001). We also observed a decrease in feeding events for kangaroos when exposed to the odor from a tiger fed kangaroo compared with all other predator-diet combinations. We observed signs of desensitization to the test odors in goats and habituation to the test odors in kangaroos over the experimental period. A better understanding of the factors involved in desensitization and habituation may increase the effectiveness of fecal odor-based repellents as a humane and nonlethal management tool for managers.     

Prenatal Alcohol Exposure Increases Postnatal Acceptability of Nicotine Odor and Taste in Adolescent Rats

Human studies indicate that alcohol exposure during gestation not only increases the chance for later alcohol abuse, but also nicotine dependence. The flavor attributes of both alcohol and nicotine can be important determinants of their initial acceptance and they both share the component chemosensory qualities of an aversive odor, bitter taste and oral irritation. There is a growing body of evidence demonstrating epigenetic chemosensory mechanisms through which fetal alcohol exposure increases adolescent alcohol acceptance, in part, by decreasing the aversion to alcohol''s bitter and oral irritation qualities, as well as its odor. Given that alcohol and nicotine have noteworthy chemosensory qualities in common, we investigated whether fetal exposure to alcohol increased the acceptability of nicotine''s odor and taste in adolescent rats. Study rats were alcohol-exposed during fetal development via the dams'' liquid diet. Control animals received ad lib access to an iso-caloric, iso-nutritive diet throughout gestation. Odorant-induced innate behavioral responses to nicotine odor (Experiment 1) or orosensory-mediated responses to nicotine solutions (Experiment 2) were obtained, using whole-body plethysmography and brief access lick tests, respectively. Compared to controls, rats exposed to fetal alcohol showed an enhanced nicotine odor response that was paralleled by increased oral acceptability of nicotine. Given the common aversive component qualities imbued in the flavor profiles of both drugs, our findings demonstrate that like postnatal alcohol avidity, fetal alcohol exposure also influences nicotine acceptance, at a minimum, by decreasing the aversion of both its smell and taste. Moreover, they highlight potential chemosensory-based mechanism(s) by which fetal alcohol exposure increases the later initial risk for nicotine use, thereby contributing to the co-morbid expression with enhanced alcohol avidity. Where common chemosensory mechanisms are at play, our results suggest broader implications related to the consequence of fetal exposure with one substance of abuse and initial acceptability of others.     

Is There Any Effect on Smell and Taste Functions with Levothyroxine Treatment in Subclinical Hypothyroidism?

Subclinical hypothyroidism has been accused for coronary heart disease, lipid metabolism disorders, neuropsychiatric disorders, infertility or pregnancy related problems with various strength of evidence. Currently there is insufficient knowledge about olfaction and taste functions in subclinical hypothyroidism. Aim of the present study is to investigate the degree of smell and taste dysfunction in patients with subclinical hypothyroidism. 28 subclinical hypothyroid patients, and 31 controls enrolled in the prospective study in Istanbul, Turkey. Subclinical hypothyroid patients were treated with L-thyroxine for 3 months. Psychophysiological olfactory testing was performed using odor dispensers similar to felt-tip pens (“Sniffin’ Sticks”, Burghart, Wedel, Germany). Taste function tests were made using "Taste Strips" (Burghart, Wedel, Germany) which are basically tastant adsorbed filter paper strip. Patients scored lower on psychophysical olfactory tests than controls (odor thresholds:8.1±1.0 vs 8.9±1.1, p = 0.007; odor discrimination:12.4±1.3 vs 13.1±0.9, p = 0.016; odor identification:13.1±0.9 vs 14.0±1.1, p = 0.001; TDI score: 33.8±2.4 vs 36.9±2.1, p = 0.001). In contrast, results from psychophysical gustatory tests showed only a decreased score for “bitter” in patients, but not for other tastes (5.9±1.8 vs 6.6±1.0, p = 0.045). Three month after onset of treatment olfactory test scores already indicated improvement (odor thresholds:8.1±1.0 vs 8.6±0.6, p<0.001; odor discrimination:12.4±1.31 vs 12.9±0.8, p = 0.011; odor identification:13.1±0.9 vs 13.9±0.8, p<0.001; TDI scores:33.8±2.4 vs 35.5±1.7, p<0.001) respectively. Taste functions did not differ between groups for sweet, salty and, sour tastes but bitter taste was improved after 3 months of thyroxin substitution (patients:5.9±1.8 vs 6.6±1.2, p = 0.045). Correlation of changes in smell and taste, with thyroid function test were also evaluated. TSH, fT4 were found have no correlation with smell and taste changes with treatment. However bitter taste found positively correlated with T3 with treatment(r: 0.445, p: 0.018). Subclinical hypothyroid patients exhibited a significantly decreased olfactory sensitivity; in addition, bitter taste was significantly affected. Most importantly, these deficits can be remedied on average within 3 months with adequate treatment.     

Chewing disability in older adults attributable to tooth loss and other oral conditions

doi: 10.1111/j.1741‐2358.2010.00412.x Chewing disability in older adults attributable to tooth loss and other oral conditions Background: This study evaluates associations between oral health‐related factors and chewing ability, and quantifies the risk contributed by each factor. Materials and methods: Chewing ability and information on number of teeth, dentures and dental problems over the last 12 months were collected by mailing questionnaires to a random sample of 60‐ to 71‐year‐olds from Adelaide, South Australia. Logistic regression was used to model oral status and oral symptoms as predictors of chewing disability, and to estimate the population‐attributable fraction. Results: A total of 444 persons responded (response rate = 68.8%). Among dentate subjects, 10.3% were chewing‐deficient, with chewing disability more prevalent (p < 0.05) among those with <21 teeth (26.4%), dentures (20.4%), painful aching in the mouth (25.4%), pain in the face (16.7%), broken/chipped teeth (15.6%), sensitive teeth (14.1%), loose teeth (37.1%), and sore gums (18.0%). Adjusted Odds ratios (OR) showed inadequate dentition (OR = 4.20), painful aching in the mouth (OR = 4.88), and presence of loose teeth (OR = 4.70) were associated with chewing disability (p < 0.01), and their population attributable fractions were 18.5%, 15.1% and 7.8% respectively. Conclusions: Loose teeth, number of teeth and pain in the mouth were associated with chewing disability, with an inadequate dentition and pain in the mouth contributing most to chewing disability in this population.     

Relationship between general health status and the change in chewing ability: a longitudinal study of the frail elderly in Japan over a 3-year period

Objectives: The aim of the present study was to identify the onset predictors of a change in chewing ability over a 3‐year period in the frail elderly. Methods: The subjects were frail elderly people living in southern Japan. Data were collected at baseline (n = 92) and 3 years later (n = 60). The dependent variable was a change in self‐rated chewing ability. The independent variables were age, gender, number of present teeth, dentition, maximum bite force (evaluated using a pressure‐sensitive foil), basic activities of daily living, self‐rated general health status, higher level of competence (evaluated using Tokyo Metropolitan Institute of Gerontology index), cognitive status (evaluated by revised Hasegawa Dementia Rating scale), and quality of life (evaluated using Philadelphia Geriatric Center morale scale) at baseline. To identify the most reliable predictors, bivariate analysis and multiple logistic regression analysis were performed, with the change of chewing ability as the dependent variable. Results: Bivariate analysis showed the change in chewing ability was significantly associated with general health status (p < 0.01), number of present teeth (p < 0.05) and maximum bite force (p < 0.01). Backward logistic regression analysis revealed that the most reliable predictor of a change in chewing ability at 3 years was general health status (odds ratio = 6.35, 95% CI = 1.69–23.88). Conclusion: The present findings suggest that general health status at baseline produces a change in chewing ability.     

Comparison of the effects of concentration, pH and anion species on astringency and sourness of organic acids

The separate effects of concentration, pH and anion species on intensity of sourness and astringency of organic acids were evaluated. Judges rated sourness and astringency intensity of lactic, malic, tartaric and citric acid solutions at three levels of constant pH varying in normality and at three levels of constant concentration varying in pH. To assess the comparative sourness and astringency of the organic acid anions of study, binary acid solutions matched in pH and titratable acidity were also rated. As pH was decreased in equinormal solutions, both sourness and astringency increased significantly (P < 0.001). By contrast, as the normality of the equi-pH solutions was increased, only sourness demonstrated significant increases (P < 0.001) while astringency remained constant or decreased slightly. At the lowest normality tested, all solutions were more astringent than sour (P < 0.05). Although lactic acid was found to be significantly more sour than citric acid (P < 0.05), no other sourness or astringency differences among the organic acid anions were noted. This study demonstrates for the first time that astringency elicited by acids is a function of pH and not concentration or anion species, and confirms that sourness is independently influenced by concentration, pH and anion species of the acid.      

Spinning-wing decoy use and reported duck harvest in Illinois: Implications for adaptive harvest management

Use of battery-powered spinning-wing decoys (SWDs) by duck hunters has generated questions as to the effect these decoys may have on duck harvests. I used data from the annual Illinois Waterfowl Hunter Survey for duck hunting seasons 1999 through 2003 to compare mallard (Anas platyrhynchos) and total duck harvest, reported days afield, and duck crippling rates between hunters using and not using SWDs. For the each of the 5 years reported, mean mallard harvest was greater among hunters using SWDs than among hunters not using the decoys and effect size was substantial (1999: F = 355.01, P < 0.001; 2000: F = 567.92, P < 0.001; 2001: F = 333.25, P < 0.001; 2002: F = 321.58, P < 0.001; 2003: F = 299.00, P < 0.001). Mean reported total ducks harvested was greater for decoy users than non-users, and I found effect sizes to be substantial for all years (1999: F = 301.80, P < 0.001; 2000: F = 607.76, P < 0.001; 2001: F = 369.49, P < 0.001; 2002: F = 321.59, P < 0.001; 2003: F = 335.82, P < 0.001). Decoy users reported hunting more days than non-users (1999: F = 71.00, P < 0.001; 2000: F = 716.50, P < 0.001; 2001: F = 486.75, P < 0.001; 2002: F = 410.72, P < 0.001; 2003: F = 466.09, P < 0.001). I observed substantial effect size for days hunted by decoy use for each year except for 1999–2000, for which effect size was typical. Hunters using SWDs reported greater crippled ducks than for hunters not using the decoys, with typical effect sizes observed for each year I examined (1999: F = 168.42, P < 0.001; 2000: F = 361.34, P < 0.001; 2001: F = 163.05, P < 0.001; 2002: F = 153.29, P < 0.001; 2003: F = 169.18, P < 0.001). I did not observe significant relationships between years of hunting experience and decoy use (R² range = 0.051–0.071). My findings support claims that SWDs lead to increased duck harvests. Recent actions by some state wildlife management agencies have resulted in a mixed approach toward regulating use of SWDs, ranging from prohibiting their use to removing all restrictions. This study seeks to provide managers with greater understanding of potential impacts of SWD use on waterfowl harvests. © 2011 The Wildlife Society.     

TASTE PERCEPTIONS AND DIETARY INTAKES OF SMOKELESS TOBACCO USERS AND NONTOBACCO USERS†

Smokeless tobacco and nontobacco users differed for certain concentrations of perceived intensities of the four solutions – significantly for sweet (P ≤ 0.008) and salty (P = 0.001). Sensitivity to salty (P = 0.02) and bitter (P = 0.11) solutions decreased with increasing hours of exposure to smokeless tobacco. Smokeless tobacco and nontobacco users rated fruits and vegetables for preference and the four taste senses differently, with a decreasing trend for sweet tastes in smokeless tobacco users with increasing hours of exposure to smokeless tobacco. Smokeless tobacco users consumed more total fat (P = 0.06) and fat per 1000 kcal (P = 0.13) than nontobacco users. Higher intakes of total fat (P = 0.005), total fat per 1000 kcal (P = 0.18), total sodium (P = 0.03) and total Vitamin E (P = 0.06) were found with increasing hours of exposure to smokeless tobacco. Although fruit and vegetable intakes did not differ between smokeless tobacco and nontobacco users, both groups should increase their consumption of fruits and vegetables.     

SNP genotypes of olfactory receptor genes associated with olfactory ability in German Shepherd dogs

To find out the relationship between SNP genotypes of canine olfactory receptor genes and olfactory ability, 28 males and 20 females from German Shepherd dogs in police service were scored by odor detection tests and analyzed using the Beckman GenomeLab SNPstream. The representative 22 SNP loci from the exonic regions of 12 olfactory receptor genes were investigated, and three kinds of odor (human, ice drug and trinitrotoluene) were detected. The results showed that the SNP genotypes at the OR10H1‐like:c.632C>T, OR10H1‐like:c.770A>T, OR2K2‐like:c.518G>A, OR4C11‐like:c.511T>G and OR4C11‐like:c.692G>A loci had a statistically significant effect on the scenting abilities (P < 0.001). The kind of odor influenced the performances of the dogs (P < 0.001). In addition, there were interactions between genotype and the kind of odor at the following loci: OR10H1‐like:c.632C>T, OR10H1‐like:c.770A>T, OR4C11‐like:c.511T>G and OR4C11‐like:c.692G>A (P < 0.001). The dogs with genotype CC at the OR10H1‐like:c.632C>T, genotype AA at the OR10H1‐like:c.770A>T, genotype TT at the OR4C11‐like:c.511T>G and genotype GG at the OR4C11‐like:c.692G>A loci did better at detecting the ice drug. We concluded that there was linkage between certain SNP genotypes and the olfactory ability of dogs and that SNP genotypes might be useful in determining dogs' scenting potential.     

Ventral pigmentation variation in the meadow spittlebug Philaenus spumarius (L.) (Hemiptera,Cicadomorpha: Cercopidae)

The meadow spittlebug Philaenus spumarius (L.) (Hemiptera, Cicadomorpha: Cercopidae) exhibits heritable colour/pattern variation on the dorsal and ventral sides of the adults. Eleven principal dorsal morphs are grouped as melanics and non-melanics according to the pigmentation of the dorsal surface. An investigation of ventral pigmentation variation in Philaenus spumarius was carried out with laboratory breeding stock obtained from Llysdinam, Wales. Analyses of the 1552 individuals, 753 females and 799 males, indicated that the pigmentation on the ventral surface of the adult individuals which vary significantly is associated with dorsal morph. Ventral parts of the dorsal melanics are usually darker than in non-melanics in both females (Kruskal-Wallis one-way ANOVA: H = 372.70, d.f. = 7, P < 0.001) and males (H = 407.36, d.f. = 7, P < 0.001). The combined “C” group morphs (flavicollis + gibbus + leuco- cephalus) are always darker than all other morphs in both sexes.     

Sociodemographics of Pet Ownership among Adolescents in Great Britain: Findings from the HBSC Study in England,Scotland, and Wales

The aim of this study was to assess the prevalence of pet ownership among adolescents in Great Britain and identify any sociodemographic differences between pet owners and non-pet owners. A total of 14,328 11-to 15-year-old adolescents from England, Scotland, and Wales were included in the analysis. Results revealed 15-year-old adolescents were significantly more likely than 11-year-old adolescents to own dogs (OR = 1.146, p < 0.001) but less likely to own fish, reptiles, or amphibians (OR = 0.629, p < 0.001), and small mammals (OR = 0.630, p < 0.001). Thirteen-year-olds were significantly more likely than 11-year-olds to own dogs (OR = 1.240, p = 0.021) and birds (OR = 1.299, p = 0.010), but significantly less likely to own fish, reptiles, or amphibians (OR = 0.795, p < 0.001). No gender differences were found. White adolescents were more likely than non-white adolescents to own all pet types. Those living in single-parent families were significantly more likely than those living with two parents to own dogs (OR = 1.186, p = 0.013) and cats (OR = 1.319, p < 0.001). Furthermore, those who reported living in stepfamilies were also more likely to own cats (OR = 1.428, p < 0.001). Adolescents with siblings were more likely to own cats (OR = 1.391, p = 0.001), fish, reptiles, or amphibians (OR = 1.220, p = 0.037) than adolescents without siblings. Adolescents with employed parents (both or one) were significantly more likely than those with unemployed parents to own dogs (OR = 1.414, p = 0.002) and birds (OR = 1.523, p = 0.018). Adolescents from high-affluence families were less likely than adolescents from low-affluence families to own dogs (OR = 0.888, p = 0.037), small mammals (OR = 0.832, p = 0.005), and birds (OR = 0.801, p = 0.046). Furthermore, family affluence differences were found in different pet types. Differences in all pet types and siblings were also found in a proxy measure of attachment to pets. This study provides evidence that pet ownership is related to several sociodemographic factors. These are relevant to take into account when performing HAI studies on adolescents.     

Seasonal changes in serum dehydroepiandrosterone,androstenedione, and testosterone levels in the squirrel monkey (Saimiri boliviensis boliviensis)

The squirrel monkey (Saimiri boliviensis boliviensis) has a well-defined breeding season during which adult males undergo androgen-dependent morphological changes, with acquisition of active spermatogenesis. To assess the hormonal events of this annual cycle, blood samples were obtained weekly from ten adult males, and serum was assayed for testosterone (T), androstenedione (ΔA), and dehydroepiandrosterone (DHEA). A significant seasonal variation was noted in mean serum T (P < 0.02), ΔA (P < 0.02), and DHEA (P < 0.001) concentrations. Mean ΔA concentrations increased from a nonbreeding season nadir of 91.4 ± 12.9 ng/ml (mean ± standard error) to a prebreeding concentration of 139 ± 10.5 ng/ml and breeding season peak of 167.5 ± 15.4 ng/ml (P < 0.05). Mean DHEA concentrations increased from a nonbreeding season nadir of 8.3 ± 0.8 to a breeding season peak of 14.3 ± 1.2 (P < 0.001). Mean T levels in the nonbreeding (52.2 ± 11.6 ng/ ml) and prebreeding season (48.6 ± 7.4) were similar. However, T significantly increased during the breeding season to 103.5 ± 12.8 ng/ml (P < 0.05). Progressive changes in body weight and morphology paralleled the rise in serum ΔA levels. The pattern of peripheral serum androgen concentrations throughout the year would suggest annual activation of the hypothalamic-pituitary-adrenal and/or hypothalamic-pituitary-gonadal axes.     

Khat Chewing Habits in the Population of the Jazan Region,Saudi Arabia: Prevalence and Associated Factors

The use of khat (Catha edulis) is a major public health and social problem that is believed to be growing globally. The khat chewing habit is prevalent in all areas of the Jazan region, Kingdom of Saudi Arabia (KSA). However, few studies have been conducted at the community level to investigate the khat chewing habits in this area. This study was conducted with the aim of assessing the prevalence and predictors of khat chewing among the Jazan community population. A cross-sectional study was conducted with a sample (n = 4,500) of the Jizani population who attended primary heath care centers in Jazan region. The participants were selected using a two-stage cluster random sampling. A structured questionnaire was used for data collection. The overall lifetime prevalence of khat chewing was 33.2% (95% CI 31.8–34.7) and was significantly higher for males 42.2% (95% CI 40.4–43.9) than for females 11.3% (95% CI 9.6–13.1) (P < 0.001). Current khat chewers accounted for 28.7% (95% CI 27.4–30.1) of the population sampled; 36.9% (95% CI 35.2–38.6) of whom were males, which is a significantly higher percentage than the 8.7% (95% CI 7.3–10.4) of current khat chewers who were females (P < 0.001). The multivariate logistic regression analysis suggests that the most important independent predictors of khat chewing were having a friend who chewed khat (OR = 20.1, P < 0.001), participant''s smoking status (OR) = 3.9, P < 0.001), friend''s smoking status (OR = 2.2, P < 0.001), gender (OR = 2.2, P < 0.001) and educational level (OR = 1.5, P < 0.05). A large proportion of the Jizani populations chew khat. Government and non-governmental organizations NGOs should design and strengthen community prevention programs to curb the high prevalence of khat use.     

Ever Try Teaching a Dog To Read? Implicit Theories of Reading Ability

ABSTRACT

When explaining academic outcomes in specific content areas, people reveal their implicit theories of academic ability. Those who hold an entity theory generally attribute differences in achievement to stable, uncontrollable factors. In contrast, those who hold an incremental theory take into account controllable psychological or environmental variables. Implicit theories affect motivation and are expected to crystallize by about fourth grade. This research examined changes in southwest suburban third graders' implicit theories of reading ability for self, others, and other species in a quasi-experimental, crossover design employing entity and incremental treatments. Seventy-one third-graders completed a 16-week reading program teaching a dog tasks that supported and challenged entity theories of what dogs can do. A therapy dog acted as our confederate because reading to dogs has been shown to improve children's reading skills, but not necessarily change their beliefs about reading ability, because beliefs are resistant to change and require personal experiences that encourage revision. Repeated measures analysis of co-variance (ANCOVA) revealed a significant change in students' theories of reading ability (F_{(1, 59)} = 60.61, p < 0.001). Students' incremental scores increased following the entity condition (F_{(1, 64)} = 1.165, p < 0.02); their entity scores decreased following both conditions (F_{(1, 59)} = 21.90, p < 0.001). Students' implicit theories of reading ability for self, other, and other species did not differ; a significant effect of belief in dogs' reading ability (F_{(1, 59)} = 29.04 p < 0.001) was observed. Implications for increasing children's reading motivation and achievement are discussed.     

Climatic influences on human body size and proportions: Ecological adaptations and secular trends

This study reevaluates the long-standing observation that human morphology varies with climate. Data on body mass, the body mass index [BMI; mass (kg)/stature (m)²], the surface area/body mass ratio, and relative sitting height (RSH; sitting height/stature) were obtained for 223 male samples and 195 female samples derived from studies published since D.F. Roberts' landmark paper “Body weight, race, and climate” in 1953 (Am. J. Phys. Anthropol. 11:533–558). Current analyses indicate that body mass varies inversely with mean annual temperature in males (r = −0.27, P < 0.001) and females (r = −0.28, P < 0.001), as does the BMI (males: r = −0.22, P = 0.001; females: r = −0.30, P < 0.001). The surface area/body mass ratio is positively correlated with temperature in both sexes (males: r = 0.29, P < 0.001; females: r = 0.34, P < 0.001), whereas the relationship between RSH and temperature is negative (males: r = −0.37, P < 0.001; females: r = −0.46, P < 0.001). These results are consistent with previous work showing that humans follow the ecological rules of Bergmann and Allen. However, the slope of the best-fit regressions between measures of body mass (i.e., mass, BMI, and surface area/mass) and temperature are more modest than those presented by Roberts. These differences appear to be attributable to secular trends in mass, particularly among tropical populations. Body mass and the BMI have increased over the last 40 years, whereas the surface area/body mass ratio has decreased. These findings indicate that, although climatic factors continue to be significant correlates of world-wide variation in human body size and morphology, differential changes in nutrition among tropical, developing world populations have moderated their influence. Am J Phys Anthropol 106:483–503, 1998. © 1998 Wiley-Liss, Inc.     

The Association between Plasma Adiponectin and Insulin Sensitivity in Humans Depends on Obesity

Objective: In humans, low plasma adiponectin concentrations precede a decrease in insulin sensitivity and predict type 2 diabetes independently of obesity. However, it is possible that the contribution of adiponectin to insulin sensitivity is not equally strong over the whole range of obesity. Research Methods and Procedures: We investigated the cross‐sectional association between plasma adiponectin levels and insulin sensitivity in different ranges of body fat content [expressed as percentage of body fat (PFAT)] in a large cohort of normal glucose‐tolerant subjects (n = 900). All individuals underwent an oral glucose tolerance test (OGTT), and 299 subjects additionally a euglycemic hyperinsulinemic clamp. In longitudinal analyses, the association of adiponectin at baseline with change in insulin sensitivity was investigated in a subgroup of 108 subjects. Results: In cross‐sectional analyses, the association between plasma adiponectin and insulin sensitivity, adjusted for age, gender, and PFAT, depended on whether subjects were lean or obese [p for interaction adiponectin × PFAT = <0.001 (OGTT) and 0.002 (clamp)]. Stratified by quartiles of PFAT, adiponectin did not correlate significantly with insulin sensitivity in subjects in the lowest PFAT quartile (R² = 0.10, p = 0.13, OGTT; and R² = 0.10, p = 0.57, clamp), whereas the association in the upper PFAT quartile was rather strong (R² = 0.36, p < 0.0001, OGTT; and R² = 0.48, p = 0.003, clamp). In longitudinal analyses, plasma adiponectin at baseline preceded change in insulin sensitivity in obese (n = 54, p = 0.03) but not in lean (n = 54, p = 0.68) individuals. Discussion: These data suggest that adiponectin is especially critical in sustaining insulin sensitivity in obese subjects. Thus, interventions to reduce insulin resistance by increasing adiponectin concentrations may be effective particularly in obese, insulin‐resistant individuals.     

Autonomic nervous system responses associated with primary tastes

The hedonic dimension of the taste sensation plays a crucial role in the control of many taste-mediated responses related to food ingestion or rejection. The purpose of this study was to evaluate the emotional reactivity associated with each primary taste (sweet, salty, sour and bitter) through analysis of the variations of autonomic nervous system (ANS) parameters. Thirty-four healthy non-smoker volunteer subjects (17 males and 17 females, mean age = 28 years) participated in the experiment. Taste stimuli were solutions of 0.3 M sucrose (sweet), 0.15 M NaCl (salty), 0.02 M citric acid (sour) and 0.00015 M quinine sulfate (bitter). Evian mineral water was used as the diluent and control (neutral taste). Throughout the test, five ANS parameters (skin potential and skin resistance, skin blood flow and skin temperature, and instantaneous heart rate) were simultaneously and continuously recorded. Results of the ANOVA evidenced a significant effect of primary taste on skin resistance amplitude (P: < 0.001) and duration (P: < 0.0001), skin temperature amplitude (P: < 0.001), skin blood flow amplitude (vasoconstriction) (P: < 0.0001) and instantaneous heart rate increase (P: < 0.0001). Skin resistance and cardiac responses were the most relevant ANS parameters to distinguish among the taste solutions. The four primary tastes could be associated with significantly different ANS responses in relation to their hedonic valence: the pleasantly connoted and innate-accepted sweet taste induced the weakest ANS responses whereas the unpleasant connoted tastes (salty, sour and bitter) induced stronger ANS responses, the innate-rejected bitter taste inducing the strongest ones. Such a neurovegetative characterization of each primary taste could provide references for the hedonic analysis of the more complex gustative sensation attached to foods.